Since 2002, a sport widely associated with rebelliousness and recklessness has been one of America's most reliable sources of medals at the Winter Olympics.

So maybe there's no call for panic. Maybe the U.S. snowboarding team will show up at the Sochi Olympics in February and, like the hard-partying actor who somehow never misses his cue, win medal after medal after medal.

ENLARGE

Shaun White
Getty Images

But suddenly there's some concern. Last weekend, the Flying Tomato, aka Shaun White, winner of the gold medal in half pipe at both the 2006 and 2010 Olympics, failed to take first in an international competition in Colorado. Worse, he wiped out. So did Kelly Clark, winner of a snowboarding gold in 2002 and bronze in 2010.

And eight months after Seth Wescott tore his ACL while filming a snowboarding movie in Alaska, the sturdiness of his knee remains a question, especially given the wild nature of Snowboardcross. In that six-man race down the mountain, Wescott won gold at the 2010 and 2006 Olympics.

But this is what American snowboarders do. They worry you. Then, typically, they dazzle you. In the past three Winter Olympics, Americans have won the overall snowboarding medal count, while winning or tying the gold-medal count.

And at stake in this sport is a large chunk of medal. In Sochi, snowboarding will account for 24 of the total medal count of almost 294.

A sport developed in America in the 1960s, snowboarding played a significant role in the U.S. renaissance in the Winter Olympics. It was introduced in the Olympics in 1998, as part of an effort by the International Olympic Committee to broaden the appeal of the Winter Games, especially among the young. That year, Americans in all disciplines won just 13 medals, or 6.3% of all medals available. By the end of the 2010 Vancouver Games, America had won 37 medals—the most of any country—representing 14.3% of the total.

Starting at the 2002 Salt Lake City Games, American snowboarders became a force. That year, they won two of four gold medals, and five of 12 overall. Four years later, it was three gold and seven overall. Then came Vancouver, when snowboarders won two of six gold medals and five of 18 overall.

In Sochi next year, the opportunities get only richer, as the IOC has added a slope-style snowboarding event, where snowboarders ride down an incline and do a series of flips and tricks off jumps.

The question is whether the U.S. is healthy and deep enough to take advantage of them. Exactly what happened to White last weekend is unclear, though afterward he told reporters that he tweaked his ankle, an injury he described as minor. At least the snowboarder who topped him was an American, Greg Bretz.

In snowboardcross, the U.S. doesn't have any substantial and healthy medal threats after Wescott. In parallel giant slalom, which doesn't involve the creativity of the other events, Americans have never done very well. And at this year's Winter X Games, they won just one of six medals in slopestyle snowboarding.

Kelly Clark, the two-time Olympic medalist and 2002 champion, said Americans are good at snowboarding because the sports' roots are here. Many of the half-pipes, rails and jumps where junior snowboarders hone their skills were first built in the U.S.

"The resorts got behind the sport in the 90s," said Clark, who started out as a ski racer but embraced snowboarding because it wasn't as intensely competitive. "That's what's catered to the progression."

After Clark saw Shannon Dunn win a bronze in 1998, she decided she wanted to follow in her footsteps. Then other women, like Elena Hight, saw Clark win her medals and decided to follow in her footsteps.

Earlier this year, Hight pulled off her much balley-hooed "Double Backside Ally Oop Rodeo" which is two back flips with a half twist while facing uphill. Whether that's enough to beat Australia's Bright, the defending Olympic champion, is another question.

While White also plans to compete in slopestyle, he will likely have a tough time knocking off Mark McMorris, the Canadian champion who won the first major slopestyle competition in Colorado last weekend.

In an interview earlier this year, McMorris said he relishes competing against White, the planet's most famous snowboarder, especially as the two have developed into the sport's premier rivalry. "It's just about determination and practice and not cracking under pressure," he said. "If I have the other guy in my head I'm not going to be focused on my riding."

Wescott ran into trouble while taking one final run in fading daylight during the filming of a snowboarding film n a glacier in Alaska.

Wescott said he got bad information from a film scout, who directed him to ride along the edge of a shadow, pick up some speed and catch air coming over a roll in the hill.

The scout didn't realize there was a crevasse immediately after the jump. Wescott went airborne at 45 miles per hour and slammed board-first directly into a wall of ice. His left leg, which is his back leg on the snowboard and holds 70% of his weight, bore the brunt of the force.

Lying on his back, Wescott knew something was wrong, though he got up and rolled down the rest of the slope and even did a few one-legged squats to assess the damage. Then a trainer did the dreaded pull-test, yanking the lower leg directly forward as Wescott sat on a chair.

When the lower leg essentially separated from his knee, Wescott knew he no longer had an ACL. Surgeons later replaced the ACL using a portion of his patella tendon so as to remove any risk that his body might reject tissue from a cadaver. He spent five months off the snow, and only during the past week has he begun to feel comfortable on his board. "I'm finally getting to the point where I can ride it into shape," he said.

Of course, just as Wescott was feeling better, Nate Holland, another American snowboardcross champion, broke his collarbone, leaving his Olympics in doubt.

Corrections and Amplifications:

The first name of snowboarder Greg Bretz was incorrectly given as Doug in an earlier version of this article.

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